You could probably do this in 1 project by using RH9's Content Categories
I've heard great things about this feature, but I think it falls slightly outside of dynamic filters.
Perhaps a better way to describe what I am trying to achieve would be as follows:
Project A will have a TOC with a Home Page and 10 content topics.
Project B will have a TOC with a Home Page and 5 content topics that are includes in Project A (6-10).
The shared topics are identitcal. I only want to have to update them in one place.
I want to be able update 6-10 in Project A and will dynamically update Project B when built.
Any ideas for how to achieve this?